Fuel injection systems are designed to deliver a mix of air and fuel into the combustion engine. Both carburetors and electronic fuel injection systems have been around quite a while, but carburetors were used early on, because electronic fuel injection technology was not perfected or practical until the mid-1980s.
A typical carburetor fuel system 100 is shown in Prior Art FIG. 1 and comprises a fuel tank 110 that is operatively coupled to a mechanical pump 120, which is operatively coupled to the carburetor 130 in the engine 140. Prior Art FIG. 2 shows an alternate embodiment 200 and comprises a fuel tank 210 that is operatively coupled to a low-pressure electric pump 220, which is operatively coupled to the carburetor 230 in the engine 240. The main issue with obtaining the best performance using a carburetor is that it can't monitor or vary the air to fuel ratio to account for different operating or atmospheric conditions. So, the best fuel to air ratio for the engine, becomes a compromise.
The Electronic Fuel Injection system or EFI is utilized to better control fuel to air ratios in order to provide better performance. Prior Art FIG. 3 shows a typical electronic fuel injection conversion fuel system 300 that comprises a fuel tank 310, a high-pressure electric pump 320 that is operatively coupled to the fuel tank 310 that directs fuel into the engine 330. A return line 340 comprising a pressure regulator 345 is directed back to the fuel tank 310. In this embodiment, the fuel tank 310 is adapted/retrofitted to add at least one baffle 315 that is required to prevent fuel sloshing. One of the disadvantages to these conventional EFI systems is that if fuel sloshes around, “fuel starvation” can occur, which is where the fuel-pick up line (not shown) loses connection/contact with the fuel. Unlike a carburetor that has an on-board fuel reserve in its bowl, the EFI arrangement can starve of fuel, as mentioned, if there is a low amount of fuel or if the fuel is sloshing around.
Another key difference between an electronic fuel injection system and a carburetor system is that the electronic system comprises a high pressure electronic pump, as opposed to the carburetor system that utilizes a low pressure pump system. So, in many instances, if one was going to convert from a conventional carburetor system to a conventional EFI system, the low pressure pumps in the carburetor system would need to be replaced by a high pressure pump, along with adding return lines to and baffles in the fuel tank.
To this end, it would be desirable to produce a fuel system for an electronic fuel injection system that achieves at least one of the following goals: a) simplifies the overall electronic fuel system arrangement, b) provides a modified system that ensures fuel is always delivered to the engine on demand, c) can be included in an original land vehicle system or may be provided in a conversion kit for existing land vehicle systems without requiring extensive modifications, and d) doesn't require a return line in the fuel injection system.